Scheduling approaches for random job shop flexible manufacturing systems

This research examines the influences that scheduling schemes and the degree of routeing flexibility have on random, job shop flexible manufacturing systems within a static environment. The first factor in the experiment includes three scheduling schemes. Two of these schemes are off-line schemes which schedule many operations prior to actual production. The first of the off-line schemes establishes an overall optimal solution, and the second off-line scheme decomposes the problem into a loading subproblem and a resulting scheduling subproblem and finds optimal solutions to both subproblems. The third scheme uses control policies and dispatching rules to establish a schedule in a real-time mode. The number of alternative machine options (i.e., the degree of routeing flexibility) is a second factor in the experiment and includes several levels. In addition, the effects of interaction between scheduling and routeing flexibility on performance are explored.